在NSString或nsmutablestring中不可能有多种颜色。我听说过一点NSAttributedString，它是在iPad SDK 3.2(或大约3.2)中引入的，并且在iPhone SDK 4.0 beta版中可用。
我想要一根有三种颜色的绳子。
我不使用3个独立的NSString的原因，是因为三个NSAttributedString子字符串的长度经常改变，所以我宁愿，不使用任何计算重新定位3个独立的NSString对象。
如果使用NSAttributedString是可能的，我怎么做以下-(如果不可能使用NSAttributedString，你会怎么做):
编辑: 记住，@"first"， @"second"和@"third"随时会被其他字符串替换。所以使用硬编码的NSRange值是行不通的。
当前回答
斯威夫特4
let combination = NSMutableAttributedString()
var part1 = NSMutableAttributedString()
var part2 = NSMutableAttributedString()
var part3 = NSMutableAttributedString()
let attrRegular = [NSAttributedStringKey.font : UIFont(name: "Palatino-Roman", size: 15)]
let attrBold:Dictionary = [NSAttributedStringKey.font : UIFont(name: "Raleway-SemiBold", size: 15)]
let attrBoldWithColor: Dictionary = [NSAttributedStringKey.font : UIFont(name: "Raleway-SemiBold", size: 15),
NSAttributedStringKey.foregroundColor: UIColor.red]
if let regular = attrRegular as? [NSAttributedStringKey : NSObject]{
part1 = NSMutableAttributedString(string: "first", attributes: regular)
}
if let bold = attrRegular as? [NSAttributedStringKey : NSObject]{
part2 = NSMutableAttributedString(string: "second", attributes: bold)
}
if let boldWithColor = attrBoldWithColor as? [NSAttributedStringKey : NSObject]{
part3 = NSMutableAttributedString(string: "third", attributes: boldWithColor)
}
combination.append(part1)
combination.append(part2)
combination.append(part3)
属性列表请参见这里的NSAttributedStringKey在苹果文档
其他回答
为了解决这类问题，我在swift中创建了一个名为Atributika的库。
let str = "<r>first</r><g>second</g><b>third</b>".style(tags:
Style("r").foregroundColor(.red),
Style("g").foregroundColor(.green),
Style("b").foregroundColor(.blue)).attributedString
label.attributedText = str
你可以在这里找到它https://github.com/psharanda/Atributika
这个方法非常简单。
let text = "This is a colorful attributed string"
let attributedText =
NSMutableAttributedString.getAttributedString(fromString: text)
attributedText.apply(color: .red, subString: "This")
//Apply yellow color on range
attributedText.apply(color: .yellow, onRange: NSMakeRange(5, 4))
更多详情请点击这里; https://github.com/iOSTechHub/AttributedString
在构建带属性字符串时，我更喜欢使用可变子类，只是为了让事情更简洁。
话虽如此，下面是如何创建一个三色带属性字符串:
NSMutableAttributedString *string = [[NSMutableAttributedString alloc] initWithString:@"firstsecondthird"];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor redColor] range:NSMakeRange(0,5)];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor greenColor] range:NSMakeRange(5,6)];
[string addAttribute:NSForegroundColorAttributeName value:[UIColor blueColor] range:NSMakeRange(11,5)];
在浏览器中输入。警告实现者
显然你不会像这样硬编码。也许你可以这样做:
NSDictionary *wordToColorMapping = ....; //an NSDictionary of NSString => UIColor pairs
NSMutableAttributedString *string = [[NSMutableAttributedString alloc] initWithString:@""];
for (NSString *word in wordToColorMapping) {
UIColor *color = [wordToColorMapping objectForKey:word];
NSDictionary *attributes = [NSDictionary dictionaryWithObject:color forKey:NSForegroundColorAttributeName];
NSAttributedString *subString = [[NSAttributedString alloc] initWithString:word attributes:attributes];
[string appendAttributedString:subString];
[subString release];
}
//display string
自iOS 7以来，你可以使用NSAttributedString与HTML语法:
NSURL *htmlString = [[NSBundle mainBundle] URLForResource: @"string" withExtension:@"html"];
NSAttributedString *stringWithHTMLAttributes = [[NSAttributedString alloc] initWithFileURL:htmlString
options:@{NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType}
documentAttributes:nil
error:nil];
textView.attributedText = stringWithHTMLAttributes;// you can use a label also
你必须添加文件"string.html"到你的项目中，html的内容可以是这样的:
<html>
<head>
<style type="text/css">
body {
font-size: 15px;
font-family: Avenir, Arial, sans-serif;
}
.red {
color: red;
}
.green {
color: green;
}
.blue {
color: blue;
}
</style>
</head>
<body>
<span class="red">first</span><span class="green">second</span><span class="blue">third</span>
</body>
</html>
现在，你可以使用NSAttributedString作为你想要的，即使没有HTML文件，例如:
//At the top of your .m file
#define RED_OCCURENCE -red_occurence-
#define GREEN_OCCURENCE -green_occurence-
#define BLUE_OCCURENCE -blue_occurence-
#define HTML_TEMPLATE @"<span style=\"color:red\">-red_occurence-</span><span style=\"color:green\">-green_occurence-</span><span style=\"color:blue\">-blue_occurence-</span></body></html>"
//Where you need to use your attributed string
NSString *string = [HTML_TEMPLATE stringByReplacingOccurrencesOfString:RED_OCCURENCE withString:@"first"] ;
string = [string stringByReplacingOccurrencesOfString:GREEN_OCCURENCE withString:@"second"];
string = [string stringByReplacingOccurrencesOfString:BLUE_OCCURENCE withString:@"third"];
NSData* cData = [string dataUsingEncoding:NSUTF8StringEncoding];
NSAttributedString *stringWithHTMLAttributes = [[NSAttributedString alloc] initWithData:cData
options:@{NSDocumentTypeDocumentAttribute:NSHTMLTextDocumentType}
documentAttributes:nil
error:nil];
textView.attributedText = stringWithHTMLAttributes;
源
- (void)changeColorWithString:(UILabel *)uilabel stringToReplace:(NSString *) stringToReplace uiColor:(UIColor *) uiColor{
NSMutableAttributedString *text =
[[NSMutableAttributedString alloc]
initWithAttributedString: uilabel.attributedText];
[text addAttribute: NSForegroundColorAttributeName value:uiColor range:[uilabel.text rangeOfString:stringToReplace]];
[uilabel setAttributedText: text];
}
